Answer: D
Step-by-step explanation:
Plot points seem linear and we can see that 25 calories were burned in 5 minutes.
Multiplying by four will have 100 calories burnt in 20 minutes
Not A because in 20 minutes 400 calories will be burnt.
Not B because if "c" is 100 calories, then "m" would have to have units of calories per minute and the 20 would have to be minutes.
Not C because the calories are increasing by the formula y = 5 + 5x, In 20 minutes only 25 calories are burned.